High-pressure steam boiler



July 26 1927.

J. BUCHLI HIGH PRESSURE STEAM BOILER Filed June 29, 1925 Patented July 26, 1927.

UNITED kSTATES JACOB BUCHLI, 0F WINTERTHUR, SWITZERLAND.

HIGH-PRESSURE STEAM BOILER.

Application filed June 29, 1925, Serial No.y

The present invention relates to improvements in high pressure water-tube boilers having an upper drum and an element for bounding the rear end of t-he irebox.

The rear wall of the reboxes of watertube boilers has been formed in various ways, for instance by means of tube elements, or by a brick wall and other means, however, besides other `disadvantages these arrangements present the drawback that they do notin most cases permit to utilize a normal lire-door.

The subject matter of the present invention is a. high pressure water-tube boiler having an upper-drum and a rear wall of the firebox wit-hin which a ring shaped member is shrunk to the upper drum and is provided in its lower part with a plurality of bores extending in the upward direction. This member is united by welding to a hollow body arranged below it, which hollow body forming the rear wall of the firebox is provided with flat walls stiffened by stay tubes and the interior of the hollow body is in communication with the upper drum by the bores in said ring shaped member.

lVith this rear wall tight oints also to the upper drum are obtained as well as an increase of the heat-ing surface owing to the circulation of water within the hollow body and it further permits the utilization of a normal fire-door.

A constructional example of the subject matter of the present invention is illustrated in the accompanying drawings, in which:

Fig. 1 shows the upper drum and the rear wall of the firebox in a vertical cross-section in the left hand side of Fig. 1 and in a front view in the right hand side of Fig. 1 and Fig. 2 shows the water-tube boiler and the rear wall of the irebox in a vertical longitu dinal section.

To the upper drum 1 the member 2 which is ring shaped in its upper part is shrunk and to the member 2 the hollow body forming the rear wall of the iirebox is welded along the seam 4. The hollow body may for instance consist of two halves 3 and 3 having flat walls `dished in along their circumference and welded together at the seams indicated in Fig. 2 at 4 and 4". An opening 5 for the ire door is provided in the hollow body 3 and the flat walls are stilened by the stay tubes 6 expanded into the walls 3 and 3.

In the member 2 bores 7 pointing in the 40,297, and in Germany February 9, 1925.

downward direction are provided which communicate at one end with the interior of the hollow body 3, 3 and at their upper end with the bores in the upper drum 1. To tighten the bores 7 with regardto the bores in the upper drum 1 tubes 8 are expanded in the upper part of the bores 7.

An insulating layer 9 is provided at the outside of the hollow body 3, 3 and is covered by sheet metal 10. 11 denotes the water tubes arranged inside the'rebox and torming the walls ofthe latter as disclosed in my Patent No. 1,576,807, dated March 16, 1926.

I claim:

1. In a high pressure water tube boiler, in combination, an upper drum, and a rear wall for the firebox comprising a member embracing said upper drum and shrunk to the latter and provided with bores in its lower part registering with bores in said upper drum, and a hollow body consisting ot' two connected halves fixed to said membervand having flat walls stifened by stay tubes, the bores in said member registering with bores in said hollow body.

2. In a high pressure water tube boiler, in combination, an upper drum, and a rear wall for the irebox comprising a member embracing said Lipper drum, shrunk to the lat. I

ter and provided with bores in its lower part registering with bores inl said drum and having tubes expanded in said bores to prevent leakage at the junction of said bores and a hollow body consisting of two connected halves fixed to said member and having flat walls stitliened by stay tubes, the bores in said member registering with bores in said hollow body.

3. In a high pressure water tube boiler, in combination, an upper drum, provided with bores in its lower part anda rear wall for the fire box comprisinga member embracing said upper drum, shrunk to the latter and provided with bores in its lower part registering with the bores in said upper drum, and having tubes expanded in said bores to prevent leakage at the junction of said bores, and a hollow body consisting of two halves welded together and welded to said member and having flat walls stiiiened by stay tubes, the bores in said member registering with bores in said hollow body.

In testimony whereof, I have signed my name to this specification.

JACOB BUCHLI. 

